I agree the HD800 is a better headphone and my long term reference. i think you may want a closed headphone more so Mike. There are some very good ones out there. I wish the PM-1 was closed.

Mee too!
Thats the first thing I realize after having them, is I whish they were closed.

There was plastic over the cups that you have to peel off, when you fist have it.
It actually simulates a closed can as it covers the grills,
but they lost a lot of bass and lower mids when playing, so you had to peel them off..

Quote:

Originally Posted by jerg

Does the PM1 sound change much if you close your hands around the grills? If not, these could be turned into great closed cans with some competent modding.

The sound almost does not change at all until you start pressing instead of just covering.
Once start pressing, it darkens slightly yet somehow retains much of the same signature.
Funny how little thw sound chages with your hands, yet with the clear plastic it totally sounds like a closed can without much bass .

This tells me that the driver only needs to breathe, and is not picky about how open the grills are (!)

Maybe with ring in between rear grill cup to extend it out a bit so as to put some dampening material and then have most of rear sealed you can attain closed status..

I am only speculating because to me it seems obvious like oppo went halfway already to design a closed can ,
But instead decided to leave it as an open can for whatever reasons..
(Like taking too long lol)Edited by Maxx134 - 4/26/14 at 5:56pm

When the cheaper PM2 comes out with more plastic body, that should make them easier to mod as well.
I can forsee a total grill seal off, and a porthole instead, drilled thru the plastics for tuning the driver air...
Edit:
The only problem would be that no one would risk such a thing without sound science because of investment involved. .Edited by Maxx134 - 4/26/14 at 6:05pm

^ The AVforum review is a bit interesting the authorEd Selley says the following

Quote:

So if these drivers are so wonderful why don’t we see them very much? Well, for starters the size of planar driver needed to generate bass as a conventional loudspeaker is not small. I recently had a pair of Magnepan planar speakers show up for test that were as near as no makes no difference six feet tall - and they were still hardly bass monsters. This is not a problem for headphones but the other big issue of planar drivers is sensitivity. Those printed drivers are considerably less efficient than a dynamic cone and this means that headphones that use planar drivers usually require very powerful headphone amps to drive them. The main proponent of the technology up until now has been American brand HiFiMan who sell an entire range of headphone amps that offer the necessary grunt to make them work.

Oppo also has a dedicated headphone amp in the works that looks seriously impressive but they have taken some care to ensure that the PM-1 is more sensitive than you might expect. The printed driver is arranged in a spiral and placed in a powerful magnetic field to reduce the energy required. They are at least partially successful too. Nobody at Grado is going to be concerned that the PM-1 is going to be more sensitive than their open backed dynamic designs but equally the Oppo can be used quite successfully from the headphone socket of an AV receiver or stereo amplifier. The fitment of a quarter inch jack which can’t be removed does suggest that portable devices might be a bridge too far though.

So I have to ask does he utilize one, or did he write this review based on collective inputs? I think there are a enough users here that think the PM-1 is not lacking on sensitivity.

I know their is some consensus that the PM1 may have rolled off trebles..
This is totally incorrect.
The PM1 do not have rolled off trebles.
They are just so very neutral to the mids level.

My own personal preference is either a brighter signature,
Or more, slightly boosted trebles than what oppo has..
Just my own preference and I would have been happy.

So I am now forced to use a foobar EQ adddon.
And now I can even elevate the signature to even hd800 brightness.
Without harshness (!)

It retains great trebles so I dunno why Oppo didn't want to show this off in final production..
Duh.

BUT:
It cannot give me what hd800 gives in terms of absolute palpable instrument separation, and ofcourse soundstage.
Anyway this should not be surprising considering none can beat the hd800 in those aspects yet.
So Otherwise PM1 is a contender.
I would not rate it higher than any top tier can, just another flavor, that of honey.
From my reading in the 560,
I feel this is a mistake if you value soundstage and speed.

no mistaken interpretation here and no drama. based on the fr measurements and comments in this thread including your comparison with the w3000anv the pm-1's highs will probably sound shelved down to me. doesn't put me off wanting to hear it for myself tho.

I now have around 50 hours of burn-in and the sound quality is still improving.

To my ears, they sound like a mix of the Stax 007mk2 and the Audeze headphones.

It's a shame that I don't have a balanced cable to try them with my Mjolnir because I'm pretty sure they could scale up with better gear. (I'm driving them with the Schiit Vali and my DAC is the Emotiva DC-1.)

I've been away from the thread for awhile, but I'm happy to hear that Matt's been convinced to order a pair. You're bound to love them based on the fact that we generally have the same preferences, but there's always that return policy if you don't. Just make sure you have something to drive them with other than your Crack and Lyr, to see what you think of them in a low-power situation. I haven't yet had the ability to run the pair I had on loan from anything but my AMC 1100, an SPL Auditor, and my iPod, so if you have some low-output mid-fi amps lying around I would like to hear what your thoughts are on the pairing.

My problem with the HD800 to PM-1 comparison is that they're clearly targeting very different sound/tonalities. I seriously can't take an opinion choosing one over the other seriously, since they're nowhere near the same sonically. Subjective, yes, but it's warm and musical vs bright and analytical, not taking all the dac/amp offsetting into account.

A more valid comparison would be the HD800 to the T1, and PM-1 to an LCD-2. You can't seriously compare something like a Grado to an HD650.Edited by Mad Lust Envy - 4/27/14 at 1:43am

I've been mulling over what other hp(s) make the best comparison to the pm-1. Hopefully I'll have a better idea of which once they get here. If the lcd2 is the most direct comparison, I'd be happy. I've always loved the sound that hp makes.